Question: Complete the recursive formula of the geometric sequence $-0.25\,,-2\,,-16\,,-128,...$. $b(1)=$
The first term is $-0.25$ and the common ratio is $8$. ${\times 8\,\curvearrowright}$ ${\times 8\,\curvearrowright}$ ${\times 8\,\curvearrowright}$ $-0.25,$ $-2,$ $-16,$ $-128,...$ This is the recursive formula of $-0.25\,,-2\,,-16\,,-128,...$. $\begin{cases} b(1)=-0.25 \\\\ b(n)=b(n-1)\cdot 8 \end{cases}$